haps safest to suppose that these insects, like the aphides, are of some use to their masters, although we are not yet in a position to surmise what this use can be.
Sleep and Cleanliness.—It is probable that all ants enjoy periods of true slumber alternating with those of activity; but actual observations on this subject have only been made in the case of two or three species. McCook says that the harvesting ants of Texas sleep so soundly that they may be pretty severely stroked with a feather without being aroused; but they are immediately awakened by a sharp tap. On awakening they often stretch their limbs in a manner precisely resembling that of warm-blooded animals, and even yawn—the latter action being "very like that of the human animal; the mandibles are thrown open with the peculiar muscular strain which is familiar to all readers; the tongue is also sometimes thrust out." The ordinary duration of sleep in this species is about three hours.
Invariably on awakening, and often at other times, the ants perform, like many other insects, elaborate processes of washing and brushing. But, unlike other insects, ants assist one another in the performance of their toilet. The author just quoted describes the whole process in the genus Atta. The cleanser begins with washing the face of her companion, and then passes on to the thorax, legs, and abdomen.
Bates also has described similar facts with regard to ants of another genus—the Ecitons.
Play and Leisure.—The life of ants is not all work, or, at least, is not so in all species. Huber describes regular gymnastic sports as practiced by the species pratensis. They raise themselves on their hind-legs to wrestle and throw pretended antagonists with their forelegs, run after each other and seem to play at hide and seek. When one is victorious in a display of strength, it often seizes all the others in the ring, and tumbles them about like nine-pins. Forel has amply confirmed these observations of Huber, and says that the chasing, struggling, and rolling together upon the ground, pulling each other in and out of the entrances, etc., irresistibly reminded him of romping